iOS 17+ · Coming soon
AstroSky tells you which nights are worth setting up the telescope, and warns you before dew or clouds ruin the session.
A free iPhone app for astrophotographers. It forecasts whether a night is worth imaging—from clouds and seeing through moonlight, dew, and target altitude. No account, no ads, and no backend. The phone talks directly to Open-Meteo and keeps sites and forecasts on the device.
Tonight
An Imaging Quality Score from 0 to 99, plus the conditions behind it: clouds by layer, seeing, transparency, temperature, dew point, ground wind, and winds aloft. Sunset, twilight, moon phase, moonrise, and moonset are calculated on the phone.
Week
Up to about eight nights, ranked from Poor to Exceptional, so you can see which evening is actually worth the setup.
Clouds dominate the score, then seeing, transparency (aerosol optical depth and dust), twilight, and moonlight. Seeing, transparency, and the score are estimates from forecast models.
Low, mid, and high cloud layers, so a thin high deck is not treated the same as a solid overcast.
Seeing, plus transparency from aerosol optical depth and dust. These are model estimates, not a measured seeing product.
Phase, moonrise, and moonset, calculated on the phone with sunset and twilight.
Temperature, dew point, ground wind, and winds aloft, so you can see a dew risk before the corrector fogs.
ECMWF and GFS run for every site, plus the best regional model for that place. If those models differ by more than 20 points, AstroSky flags it.
Sites
Search by place name or coordinates, or use your location. Each site has a Bortle class from 1 to 9 that you set yourself. There is no light-pollution map.
Targets
A built-in deep-sky list—Andromeda, Orion, Lagoon, and others—ranked by altitude for that night.
Rig
A short catalog (EdgeHD 8″, Esprit 100, RedCat 51; ASI2600MC Pro, ASI294MC Pro) used for dew timing and session notes.
A heads-up the evening before a good night, dew warnings, incoming high clouds, and model disagreement. Quiet hours are 7 AM–3 PM. Alerts cover the selected site and refresh when you open the app or when iOS runs a background refresh.
Weather data by Open-Meteo.com (CC BY 4.0). Aerosols from Copernicus CAMS. Astronomy—sun, moon, and target altitude—is calculated on the device.
Check the sky before you set up. Seeing, transparency, and the Imaging Quality Score are estimates from forecast models, not a measured seeing product.
Coming soon on the App Store. We’ll add the link here when it’s live.
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